Hp Integrity NonStop J-Series Manuel d'utilisateur télécharger pdf (Page 57)

100

101

DEVELOPING A DATA BASE

Drawing the Relationship Between Classes of Information

Sample Data for Dependents

empnum

0001

0002

0004

•••

dependent-name

•••

Jane Jones

Bill Jones

Mark Jones

Judy Martin

Leslie Monte

David Monte

Sue Monte

relationship

•••

dependent-age

•••

Figure 3-5. Dependents Class with Repeating Data

You can remove this repeating data from the dependents class by

using a technique called "normalization." To normalize the

dependents data, you could include "empnum" with each occurrence

of "dependent-name," "relationship," and "dependent-age." Figure

3-6 illustrates how the sample dependent data appears when you

eliminate repeating data.

3-6

1 2 ... 52 53 54 55 56 57 58 59 60 61 62 ... 361 362

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Hp Integrity NonStop J-Series Manuel d'utilisateur Page 57

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